The most important topics Gates discussed were related to the Foundation's work. Gates believes that, in spite of the efforts of the anti-vax crowd, the eradication of polio is less than six years away. After polio, the focus will be measles and malaria.

Gates also stressed the importance of investment into the development of energy sources that don't produce carbon dioxide.

However, technology questions were, of course, inevitable. Luckily Gates was happy to answer them. When asked "Windows 7 or Windows 8?" the response was simple: "Higher is better." He thinks Windows 8 is a "huge advance," though he suggested it will only really shine when hardware and apps that take advantage of it come out.

His biggest technology disappointment? The failure in bringing WinFS to market. WinFS was to be a database-like storage layer for Windows that would provide synchronization and structured storage in a system-wide, application independent way. The WinFS project was originally to be part of Windows "Longhorn" before being scrapped as part of the reset that ultimately produced Windows Vista.

Gates hasn't given up on that particular dream, however. He argued WinFS-like technology would be a feature of future software, with structured cloud storage to store your data and partial replicas of that data on local devices.

He still programs from time to time—C, C#, and "some Basic"—though says he doesn't get to do it as much as he would like. Gates also expressed surprise that programming languages fundamentally haven't made programming any simpler, adding "It would be great if most high school kids were exposed to programming...."

The Microsoft chairman also entertained reddit's more trivial side. What do you give the man who has (or at least, can afford) everything? Books. What cheap thing still gives him pleasure? Cheeseburgers and kids. Kids aren't traditionally thought of as cheap, but Gates purports to prefer the old-fashioned method of stork delivery, and this apparently keeps the cost down.